...but rather advances in lens design which are allowing affordable, very-fast lenses to be sharp wide open, coupled with the dSLR boom which has opened up a wider market for such lenses.

Whereas in the past, many fast lenses were noticeably less-sharp unless stopped down one or two stops (and even older reviews, written before the "technical review" era would acknowledge this), we're now seeing many fast lenses that are beautifully-sharp wide-open. I don't think this is universally a bad thing.

I don't think it's a bad thing either -if- they aren't giving up something else to get this razor sharpness.

From what I am seeing with these 2 sigma ART lenses, they did give up some -rendering- to get this level of focus plane sharpness. Enough so that I'm not interested in either of these latest sigma primes, in fact I purchased my 58 after I saw the initial round of test shots from the sigma and trust me, I wanted to like this much less expensive lens. For a 35, I ended up buying the MF zeiss when I really would have preferred an AF lens.

My original point was, I am personally OK with a lens not being the sharpest knife in the drawer if it brings other less technical, what I see as positive things, to the table. What I see on the online forums is "the masses" have a tunnel vision focus on sharpness and what it looks like zoomed in at 100%.